Saturday, January 22, 2011

Some Important Concepts System

To more easily understand further the meaning system and information system is necessary to remember some important concepts in the development of the system, namely:

1. Decomposition
To analyze and understand thoroughly a large system, it usually takes a long time. To facilitate this work used the concept of decomposition. Decomposition is a division of systems into components of smaller (subsystems). Decomposition has several advantages, including:
  • Analysts to more easily manage and analyze each subsystem in more detail.
  • On the development of the system, the system can be decomposed into several modules. Development of several modules can be done in parallel with no dependency requirement between modules are built.

2. Modularity
The concept of modularity associated with decomposition. At the time of decomposition, it is expected that a large system is divided into sub-systems to be relatively the same size. With these modules the workload of the system developed can be distributed evenly on all available resources. System development so much simpler because it only focused on one module first, and do the integration between modules.

3. Coupling
And modules that we get, sometimes found some modules that have dependencies with other modules. In such cases, the modules are interdependent must be paired (in-couple). In this way can be known modules that can work independently and modules that should be completed first before the other modules work.

4. Cohesion
Of the coupling between modules, we can get the module groups with similar characteristics. Here comes the concept of cohesion in which the module should be analyzed together with the mutual cohesion of the group module.

Friday, January 21, 2011

System That Bad

To avoid developing a bad system, keep in mind some of the traits and the bad system:
a. Not meet user needs
b. Poor performance
c. Rehabilitation of low
d. Low usability
e. Examples of difficulty:
  • Not scheduled.
  • No budget plan.
  • Can walk = 100% over budget or schedule.

Wednesday, January 19, 2011

Definitions Subsystem

A complex system is usually composed of several subsystems. Subsystem can be described as a system within a larger system. For example:
Automobile is a system comprising several subsystems and the following:
  1. Machine system
  2. Body system
  3. Wheel system
Each subsystem can be made ​​and some subsistems the following:
Machine systems: systems carburetor, generator systems, fuel systems, etc.

Sunday, January 9, 2011

Characteristics Of System

In order to understand or develop a system, it is necessary to distinguish the elements and systems that shape it. Here are the characteristics of a system that can distinguish a system with other systems:
  1. Boundary. Depiction and an element or elements which are included in the system and which are outside the system.
  2. Environment. Everything outside the system, providing environmental assumptions, constraints, and input to a system.
  3. Input. Resources (data, materials, equipment, energy) and the environment that is consumed and manipulated by a system.
  4. The output. Resource or product (information, reports, documents, computer screen display, finished goods) are provided for the system environment by the activities in a system. Component activities or processes in a system that transforms input into the form of semi-finished (output). This component can be a subsystem and a system.
  5. Interface. The place where the component or system and its environment to meet or interact.
  6. Storage. Area occupied and used for temporary and permanent storage and information, energy, raw materials, and so forth. A storage buffer between the media divulging these components work with various levels that exist and allow the different components and a variety of the same data.